Results 1 to 7 of 7

Math Help - Vectors in 3D

  1. #1
    Junior Member
    Joined
    Apr 2010
    Posts
    60

    Vectors in 3D

    Please find the question attached.
    I started solving this by taking the first point as x1,y1,z1 and second one as x2,y2,z2
    and so the distance between these points to B is *sqrt*14.
    Although this method doesn't seem to be working. Any help/hint on how to proceed with this question will be much appreciated.
    Attached Thumbnails Attached Thumbnails Vectors in 3D-vectors.jpg  
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,657
    Thanks
    1607
    Awards
    1

    Re: Vectors in 3D

    You need to find where the y-axis insects the sphere (x+1)^2+(y+1)^2+(z-2)^2=14~.
    Recall that the y-axis is (0,t,0)~.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Apr 2010
    Posts
    60

    Re: Vectors in 3D

    So i put y=t? and x=0 and z=0?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,657
    Thanks
    1607
    Awards
    1

    Re: Vectors in 3D

    Quote Originally Posted by kandyfloss View Post
    So i put y=t? and x=0 and z=0?
    Indeed, yes. Solve for t.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Junior Member
    Joined
    Apr 2010
    Posts
    60

    Re: Vectors in 3D

    Quote Originally Posted by Plato View Post
    Indeed, yes. Solve for t.
    So i get t(^2) + 2t -13=0
    And it seems my values for t are going to be in fraction, and the answer is in whole numbers.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,657
    Thanks
    1607
    Awards
    1

    Re: Vectors in 3D

    Quote Originally Posted by kandyfloss View Post
    So i get t(^2) + 2t -13=0
    I get t^2+2t-8=0
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Junior Member
    Joined
    Apr 2010
    Posts
    60

    Thumbs up Re: Vectors in 3D

    Quote Originally Posted by Plato View Post
    I get t^2+2t-8=0
    oh yes, sorry. I'm kind of out of my mind today. Thanks a lot!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: November 15th 2011, 05:10 PM
  2. Replies: 3
    Last Post: June 30th 2011, 08:05 PM
  3. Replies: 2
    Last Post: June 18th 2011, 10:31 AM
  4. [SOLVED] Vectors: Finding coefficients to scalars with given vectors.
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: January 23rd 2011, 12:47 AM
  5. Replies: 4
    Last Post: May 10th 2009, 06:03 PM

Search Tags


/mathhelpforum @mathhelpforum